Delayed Fluorescence Compound, and Organic Light Emitting Diode and Display Device Using the Same

ABSTRACT

Embodiments relate to a delayed fluorescence compound of 
     
       
         
         
             
             
         
       
     
     The excitons in the triplet state are engaged in emission such that the emitting efficiency of the delayed fluorescent compound is increased. Embodiments also relate to a display device with an organic light emitting diode (OLED) that includes the delayed fluorescence compound.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. patentapplication Ser. No. 15/920,358, filed on Mar. 13, 2018, which is acontinuation application of U.S. patent application Ser. No. 14/938,723,filed on Nov. 11, 2015, which claims priority to and the benefit ofRepublic of Korea Patent Application No. 10-2014-0156946 filed on Nov.12, 2014, Republic of Korea Patent Application No. 10-2014-0169004 filedon Nov. 28, 2014, Republic of Korea Patent Application No.10-2014-0169077 filed on Nov. 28, 2014, Republic of Korea PatentApplication No. 10-2015-0141568 filed on Oct. 8, 2015, Republic of KoreaPatent Application No. 10-2015-0141569 filed on Oct. 8, 2015, andRepublic of Korea Patent Application No. 10-2015-0141570 filed on Oct.8, 2015, all of which are hereby incorporated by reference in theirentirety.

BACKGROUND OF THE INVENTION Field of the Invention

Embodiments of the invention relate to an organic light emitting diode(OLED) and more particularly to a delayed fluorescence compound havingexcellent emitting efficiency and an OLED and a display device using thedelayed fluorescence compound.

Discussion of the Related Art

The requirements of large-size display devices have led to developmentsin flat panel display devices as an image displaying device. Among theflat panel display devices, the OLED has rapidly developed.

In the OLED, when the electron from a cathode, which serves as anelectron-injecting electrode, and a hole from an anode, which serves asa hole-injecting electrode, are injected into an emitting materiallayer, the electron and the hole are combined and become extinct suchthat the light is emitted from the OLED. A flexible substrate, forexample, a plastic substrate, can be used as a base substrate for theOLED, and the OLED has excellent characteristics of driving voltage,power consumption, and color purity.

The OLED includes a first electrode as an anode on a substrate, a secondelectrode as a cathode facing the first electrode, and an organicemitting layer therebetween.

To improve the emitting efficiency, the organic emitting layer mayinclude a hole injection layer (HIL), a hole transporting layer (HTL),an emitting material layer (EML), an electron transporting layer (HTL),and an electron injection layer (EIL) sequentially stacked on the firstelectrode.

The hole is transferred into the EML from the first electrode throughthe HIL and the HTL, and the electron is transferred into the EML fromthe second electrode through the EIL and the ETL.

The electron and the hole are combined in the EML to generated excitons,and the excitons are transited from an excited state to a ground statesuch that light is emitted.

The external quantum efficiency of the emitting material for the EML canbe expressed by:

η_(ext)=η_(int)×Γ×Φ×η_(out-coupling)

In the above equation, “η_(int)” is the internal quantum efficiency, “Γ”is the charge balance factor, “Φ” is the radiative quantum efficiency,and “η_(out-coupling)” is the out-coupling efficiency.

The charge balance factor “r” means a balance between the hole and theelectron when generating the exciton. Generally, assuming 1:1 matchingof the hole and the electrode, the charge balance factor has a value of“1”. The radiative quantum efficiency “Φ” is a value regarding aneffective emitting efficiency of the emitting material. In thehost-dopant system, the radiative quantum efficiency depends on afluorescent quantum efficiency of the dopant.

The internal quantum efficiency “η_(int)” is a ratio of the excitonsgenerating the light to the excitons generated by the combination ofholes and electrons. In the fluorescent compound, a maximum value of theinternal quantum efficiency is 0.25. When the hole and the electron arecombined to generate the exciton, a ratio of singlet excitons to tripletexcitons is 1:3 according to the spin structure. However, in thefluorescent compound, only the singlet excitons, excluding the tripletexcitons, are engaged in the emission.

The out-coupling efficiency “η_(out-coupling)” is a ratio of the lightemitted from the display device to the light emitted from the EML. Whenthe isotropic compounds are deposited in a thermal evaporation method toform a thin film, the emitting materials are randomly oriented. In thisinstance, the out-coupling efficiency of the display device may beassumed to be 0.2.

Accordingly, the maximum emitting efficiency of the OLED, including thefluorescent compound as the emitting material, is less thanapproximately 5%.

To overcome the disadvantage of the emitting efficiency of thefluorescent compound, the phosphorescent compound, in which both singletexcitons and triplet excitons are engaged in emission, has beendeveloped for the OLED.

The red and green phosphorescent compound having a relatively highefficiency are introduced and developed. However, there is no bluephosphorescent compound meeting the requirements in emitting efficiencyand reliability.

SUMMARY OF THE INVENTION

Accordingly, the embodiment of the invention is directed to a delayedfluorescence compound and an OLED and a display device using the samethat substantially obviate one or more of the problems due tolimitations and disadvantages of the related art.

An objective of the embodiment of the invention is to provide a delayedfluorescence compound having high emitting efficiency.

Another objective of the embodiment of the invention is to provide anOLED and a display device having an improved emission efficiency.

Additional features and advantages of the invention will be set forth inthe description which follows, and in part will be apparent from thedescription, or may be learned by practice of the invention. Theobjectives and other advantages of the invention will be realized andattained by the structure particularly pointed out in the writtendescription and claims hereof as well as the appended drawings.

To achieve these and other advantages and in accordance with the purposeof the embodiments of the invention, as embodied and broadly describedherein, an aspect of an embodiment of the invention provides a delayedfluorescence compound of Formula 1 or Formula 2, an encapsulation filmon the organic light emitting diode, and a cover window on theencapsulation film. Formulas 1 and 2 are given by:

wherein each of m and n is 1 or 0, and X₁ is selected from Formula 3,wherein each of L₁ and L₂ is independently selected from Formula 4, andX₂ and Y are respectively selected from Formulas 5 and 6. Formulas 3-6are given by:

wherein each of R₁ to R₄ in the Formula 3 is independently selected fromsubstituted or non-substituted aryl, and each of R₅ and R₆ in theFormula 4 is independently selected from hydrogen or C1 alkyl throughC10 alkyl, and wherein R₇ in the Formula 5 is selected from hydrogen orphenyl.

In another aspect of the embodiment of the invention provided is anorganic light emitting diode including a first electrode, a secondelectrode facing the first electrode, and an organic emitting layerbetween the first and second electrodes and including a delayedfluorescence compound of Formula 1 or Formula 2, an encapsulation filmon the organic light emitting diode, and a cover window on theencapsulation film. Formulas 1 and 2 are given by:

wherein each of m and n is 1 or 0, and X₁ is selected from Formula 3,wherein each of L₁ and L₂ is independently selected from Formula 4, andX₂ and Y are respectively selected from Formulas 5 and 6. Formulas 3-6are given by:

wherein each of R₁ to R₄ in the Formula 3 is independently selected fromsubstituted or non-substituted aryl, and each of R₅ and R₆ in theFormula 4 is independently selected from hydrogen or C1 alkyl throughC10 alkyl, and wherein R₇ in the Formula 5 is selected from hydrogen orphenyl.

In another aspect of the embodiment of the invention provided is adisplay device including a substrate; an organic light emitting diode onthe substrate and including a first electrode, a second electrode facingthe first electrode and an organic emitting layer between the firstelectrode and the second electrode, the organic emitting layer includinga delayed fluorescence compound of Formula 1 or Formula 2, anencapsulation film on the organic light emitting diode, and a coverwindow on the encapsulation film. Formulas 1 and 2 are given by:

wherein each of m and n is 1 or 0, and X₁ is selected from Formula 3,wherein each of L₁ and L₂ is independently selected from Formula 4, andX₂ and Y are respectively selected from Formulas 5 and 6. Formulas 3-6are given by:

wherein each of R₁ to R₄ in the Formula 3 is independently selected fromsubstituted or non-substituted aryl, and each of R₅ and R₆ in theFormula 4 is independently selected from hydrogen or C1 alkyl throughC10 alkyl, and wherein R₇ in the Formula 5 is selected from hydrogen orphenyl.

It is to be understood that both the foregoing general description andthe following detailed description are by example and explanatory andare intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention.

FIG. 1 is a view illustrating an emission mechanism of a delayedfluorescence compound according to the present disclosure.

FIGS. 2A to 2F are views respectively illustrating a molecular structureof a compound having a carbazole electron donor moiety.

FIGS. 3A to 3F are views respectively illustrating a molecular structureof a compound having an acridine electron donor moiety.

FIGS. 4A to 4J are graphs showing a delayed fluorescent property of adelayed fluorescence compound according to the present disclosure.

FIG. 5 is a schematic cross-sectional view of an OLED according to thepresent disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The meanings of terms described in the present specification should beunderstood as follows.

The singular forms should be understood as including the plural forms aswell unless the context clearly indicates otherwise. The terms “first”,“second”, and the like are used to discriminate any one element fromother elements and the scope of the present invention is not intended tobe limited by these terms. The terms “comprises” “includes” and the likeshould be understood as not precluding the presence or addition of oneor more other features, integers, steps, operations, elements,components, or combinations thereof. The term “at least one” should beunderstood as including all combinations that may be suggested from oneor more associated items. For example, the meanings of “at least oneselected from a first item, a second item, and a third item” includesnot only each of the first item, the second item, and the third item,but also all combinations of these items that may be suggested from twoor more ones of the first item, the second item, and the third item. Inaddition, when any one element is referred to as being “on” anotherelement, it can be directly on the upper surface of the other element ora third intervening element may also be present.

Reference will now be made in detail to example embodiments, examples ofwhich are illustrated in the accompanying drawings.

A delayed fluorescence compound of the present disclosure has Formula1-1 or Formula 1-2 of the followings.

where each of “m” and “n” is 0 (zero) or 1.

Namely, as shown in Formula 2-1, the delayed fluorescence compound has astructure in which an electron donor moiety of acridine is combined orlinked to an electron acceptor moiety X₁ with a linker L₁ therebetween.Alternatively, as shown in Formula 2-2, the delayed fluorescencecompound has a structure in which an electron donor moiety of acridineis directly combined or linked to an electron acceptor moiety X₁ withouta linker.

Alternatively, as shown in Formula 2-3, the delayed fluorescencecompound has a structure in which a first electron donor moiety ofacridine and a second electron donor moiety Y, which is equal to ordifferent from the first electron donor moiety, are combined or linkedto an electron acceptor moiety X₂ with a linker L₂ therebetween.Alternatively, as shown in Formula 2-4, the delayed fluorescencecompound has a structure in which a first electron donor moiety ofacridine and a second electron donor moiety Y, which is equal to ordifferent from the first electron donor moiety, are directly combined orlinked to an electron acceptor moiety X₂ without a linker.

In the Formulas 2-1 and 2-2, the electron acceptor moiety X₁ is selectedfrom substituted or non-substituted triazine, substituted ornon-substituted dibenzothiophene, substituted or non-substituted4-azabenzimidazole, or substituted or non-substituted benzimidazole. Forexample, the electron acceptor moiety X₁ may be selected from materialsin Formula 3 of the following.

In the Formula 3, each of R₁ to R₄ is independently selected fromhydrogen or substituted or non-substituted aryl. For example, each of R₁to R₄ may be selected from hydrogen or non-substituted phenyl.

In the Formulas 1-1, 1-2, 2-1, and 2-3, each of L₁ and L₂ as the linkeris substituted or non-substituted benzene. For example, each of L₁ andL₂ may be a material in Formula 4 of following.

In Formula 4, each of R₅ and R₆ is independently selected from hydrogenor C1 to C10 alkyl. For example, each of R₅ and R₆ may be hydrogen ormethyl.

In the Formulas 1-2, 2-3, and 2-4, the electron acceptor moiety X₂ isselected from substituted or non-substituted phenyltriazine,dibenzothiophenesulfone, diphenylsulfone, quinoxaline, thieno pyrazine,or their derivatives. For example, the electron acceptor moiety X₂ maybe selected from materials in Formula 5 of the following.

In the Formula 5, R₇ is selected from hydrogen or phenyl.

In the Formulas 1-2, 2-3, and 2-4, the second electron donor moiety Y isselected from materials, which is capable of injecting a hole, such ascarbazole, triphenyl amine, acridine, or their derivatives. Namely, thesecond electron donor moiety Y is selected from substituted ornon-substituted carbazole, substituted or non-substituted triphenylamine, or substituted or non-substituted acridine. For example, thesecond electron donor moiety Y may be selected from materials in Formula6 of the following.

Since the delayed fluorescence compound includes the electron donormoiety and the electron acceptor moiety with or without another electrondonor moiety, the charge transfer is easily generated in the moleculeand the emitting efficiency is improved. In addition, the dipole fromthe first and second electron donor moieties to the electron acceptormoiety is generated such that the dipole moment in the molecule isincreased. As a result, the emitting efficiency is further improved.

Moreover, in the delayed fluorescent compound of the present disclosure,the excitons in the triplet state are engaged in the emission such thatthe emitting efficiency of the delayed fluorescent compound isincreased.

Further, since acridine, which has a hexagonal structure, is used as theelectron donor moiety, a steric hindrance between the electron donormoiety and the electron acceptor moiety is increased, and a dihedralangle between the acridine electron donor moiety and the electronacceptor moiety is also increased. Accordingly, the generation ofconjugation between the electron donor moiety and the electron acceptormoiety is limited, and the highest occupied molecular orbital (HOMO) andthe lowest unoccupied molecular orbital (LUMO) is easily separated. As aresult, the emitting efficiency of the delayed fluorescent compound isfurther increased.

In the delayed fluorescence compound of the present disclosure, theelectron donor moiety and the electron acceptor moiety are combined orlinked in the molecule such that an overlap between HOMO and LUMO isreduced. As a result, a field activated complex is generated, and theemitting efficiency of the delayed fluorescence compound is improved.

Since a gap or a distance between the electron donor moiety and theelectron acceptor moiety is increased due to the linker, an overlapbetween HOMO and LUMO is reduced such that a gap (ΔE_(ST)) between thetriple energy and the singlet energy is reduced.

In addition, due to the steric hindrance of the linker, the red shiftproblem in the light emitted from the emitting layer including thedelayed fluorescence compound is decreased or minimized. Namely, theemitting layer with the delayed fluorescence compound of the presentdisclosure provides deep blue emission.

Referring to FIG. 1, which is a view illustrating an emission mechanismof a delayed fluorescence compound according to the present disclosure,in the delayed fluorescence compound of the present disclosure, thetriplet excitons as well as the singlet excitons are engaged in theemission such that the emitting efficiency is improved.

Namely, the triplet exciton is activated by a field, and the tripletexciton and the singlet exciton are transferred into an intermediatedstate “I₁” and transited into a ground state “S_(O)” to emit light. Inother words, the singlet state “S₁” and the triplet state “T₁” aretransited into the intermediated state “I₁” (S₁->I₁<-T₁), and thesinglet exciton and the triplet exciton in the intermediated state “I₁”are engaged in the emission such that the emitting efficiency isimproved. The compound having the above emission mechanism may bereferred to as a field activated delayed fluorescence (FADF) compound.

In the related art fluorescence compound, since the HOMO and the LUMOare dispersed throughout an entirety of the molecule, theinterconversion of the HOMO and the LUMO is impossible. (Selection Rule)

However, in the FADF compound, since the overlap between the HOMO andthe LUMO in the molecule is relatively small, the interaction betweenthe HOMO and the LUMO is small. Accordingly, changes of the spin stateof one electron do not affect other electrons, and a new charge transferband, which does not comply with the Selection Rule, is generated.

Moreover, since the electron donor moiety and the electron acceptormoiety are spatially spaced apart from each other in the molecule, thedipole moment is generated in a polarized state. In the polarized statedipole moment, the interaction between the HOMO and the LUMO is furtherreduced such that the emission mechanism does not comply with theSelection Rule. Accordingly, in the FADF compound, the transition fromthe triplet state “T₁” and the singlet state “S₁” into the intermediatedstate “I₁” can be generated such that the triplet exciton can be engagedin the emission.

When the OLED is driven, the intersystem transition (intersystemcrossing) from 25% singlet state “S₁” excitons and 75% triplet state“T₁” excitons to the intermediated state “I₁” is generated, and thesinglet and triplet excitons in the intermediated state “I₁” aretransited into the ground state to emit light. As a result, the FADFcompound has a theoretic quantum efficiency of 100%.

For example, the delayed fluorescence compound of the present inventionmay be one of compounds in Formula 7.

As mentioned above, the delayed fluorescence compound of the presentinvention includes an acridine electron donor moiety such that a sterichindrance between the electron donor moiety and the electron acceptormoiety is increased, and a dihedral angle between the acridine electrondonor moiety and the electron acceptor moiety is also increased.

FIGS. 2A to 2F are views respectively illustrating a molecular structureof a compound having a carbazole electron donor moiety anddibenzothiophenesulfone as an electron acceptor moiety, and FIGS. 3A to3F are views respectively illustrating a molecular structure of acompound having an acridine electron donor moiety anddibenzothiophenesulfone as an electron acceptor moiety.

Referring to FIGS. 2A to 2F, in the compound including carbazole as theelectron donor moiety, the dihedral angle between the electron donormoiety and the electron acceptor moiety (or the linker) is about 44degrees.

On the other hand, referring to FIGS. 3A to 3F, in the compoundincluding acridine as the electron donor moiety, the dihedral anglebetween the electron donor moiety and the electron acceptor moiety (orthe linker) is about 90 degrees.

Namely, when acridine is used as the electron donor moiety, the dihedralangle between the acridine electron donor moiety and the electronacceptor moiety is increased, and the generation of conjugation betweenthe electron donor moiety and the electron acceptor moiety (or thelinker) is limited. As a result, in comparison to the compound includingthe carbazole electron donor moiety, the HOMO and the LUMO in thecompound including the acridine electron donor moiety is easilyseparated such that the emitting efficiency is further improved.

Synthesis

1. Synthesis of Compound 1

(1) Compound “a”

In the N₂ gas purging system, 2,8-dibromodibenzothiophene (14.6 mmol)and acetic acid solvent were mixed and stirred. Hydrogen peroxide (64.8mmol) was added and stirred in the room temperature for about 30minutes, and the mixture was refluxed and stirred for 12 hours or more.After completion of the reaction, distilled water (50 ml) was added andstirred to wash. After filtering the mixture, the solids was mixed withexcess hydrogen peroxide and stirred to wash for 30 to 60 minutes. Thesolids was washed by distilled water and filtered and dried such thatcompound “a” in white solid was obtained. (yield: 90%)

(2) Compound “b”

In the N₂ gas purging system, N-phenylanthranilic acid (46.9 mmol) andmethanol solvent were mixed and stirred. The mixture was additionallystirred for 10 minutes under a temperature of 0° C., and thionylchloride (21.2 mmol) was slowly dropped. The mixed solution was stirredfor 12 hours or more under a temperature of 90° C. After completion ofthe reaction, the solvent was removed, and the mixed solution wasextracted by distilled water and ethylacetate. Moisture was removed fromthe extracted organic layer by using magnesium sulfate, and the solventwas removed. The resultant was wet-refined by column-chromatographyusing hexane and ethylacetate such that compound “b” of dark yellowliquid was obtained. (yield: 81%)

(3) Compound “c”

In the N₂ gas purging system, compound “b” (38.1 mmol) andtetrahydrofuran solvent was stirred. Methyl magnesium bromide (4.6equivalent) was slowly dropped in the solution, and the solution wasstirred and reacted for 12 hours or more under the room temperature.After completion of the reaction, distilled water was slowly added, andthe solution was extracted by ethylacetate. Moisture was removed fromthe extracted organic layer by using magnesium sulfate, and the solventwas removed. The resultant was wet-refined by column-chromatographyusing hexane and ethylacetate such that compound “c” of yellow liquidwas obtained. (yield: 87%)

(4) Compound “d”

In the N₂ gas purging system, compound “c” (33.1 mmol) was put intoexcess phosphoric acid solvent (160 ml), and the solution was stirredunder the room temperature. The solution was additionally stirred for 16hours or more, and distilled water (200 to 250 ml) was slowly added. Thesolution was stirred for 0.5 to 1 hour, and the precipitated solid wasfiltered. The filtered solid was extracted by using sodium hydroxideaqueous solution and dichloromethane solvent. Moisture was removed fromthe extracted organic layer by using magnesium sulfate, and the organicsolvent was removed such that compound “d” of white solid was obtained.(yield: 69%)

(5) Compound “e”

In the N₂ gas purging system, compound “a” (1.0 equivalent) wasdissolved in toluene solvent, and phenylboronic acid (0.9 equivalent)was added. K₂CO₃ (4 equivalent) was dissolved in distilled water andadded into the mixed solution. Tetrahydrofuran solvent was added, andpalladium (0.05 equivalent) was added. The mixture was refluxed andstirred under a temperature of 80° C. After completion of the reaction,the mixture was extracted by using ethylacetate solvent and distilledwater, and moisture was removed from the extracted organic layer byusing magnesium sulfate. Remained organic solvent was removed, and theresultant was wet-refined by column-chromatography using ethylacetateand hexane such that compound “e” of solid was obtained. (yield: 68%)

(6) Compound 1

In the N₂ gas purging system, compound “e” (1.0 equivalent), compound“d” (1.1 equivalent), Pd(OAc)₂ (0.019 equivalent), P(t-Bu)₃ (50 wt %,0.046 equivalent), and sodium tert-butoxide (1.9 equivalent) were addedinto toluene solvent and stirred. The solution was refluxed and stirredfor 12 hours under a temperature of 120° C. After completion of thereaction, the solution was cooled in room temperature and extracted bywater and ethylacetate. Moisture was removed from the extracted organiclayer by using magnesium sulfate, and the solvent was removed. Theresultant was wet-refined by column-chromatography using hexane andethylacetate such that compound 1 was obtained. (yield: 55%)

2. Synthesis of Compound 2

(1) Compound “f”

In the N₂ gas purging system, compound “d” (23.9 mmol),1,4-dibromobenzene (35.8 mmol), palladium(II)acetate (2 mol %),tri-tert-butylphosphate (5 mol %), and sodium-tert-butoxide (2.03equivalent) was added into toluene solvent and stirred. The mixedsolution was refluxed and stirred for 12 hours. After completion of thereaction, the solution was extracted by using distilled water andethylacetate. Moisture was removed from the extracted organic layer byusing magnesium sulfate, and the solvent was removed. The resultant waswet-refined by column-chromatography using hexane and ethylacetate suchthat compound “f” of dark yellow liquid was obtained. (yield: 81%)

(2) Compound “g”

In the N₂ gas purging system, compound “f” (1.0 equivalent),bis(pinacolate)diboron (1.2 equivalent),[1,1-bis(diphenylphosphineo)ferrocene]palladium(II), dichloridedichloromethane, 1,1-bis(diphenylphosphino)ferrocene, and potassiumacetate were added into 1,4-dioxane/toluene (1:1) solvent in thelight-shielded flask and stirred. After bubbles disappeared, thesolution was stirred for 17 hours under a temperature of 120° C. Aftercompletion of the reaction, the solution was cooled in room temperature,and the solvent was removed. The resultant was washed by toluene andrefined such that compound “g” was obtained. (yield: 90%)

(3) Compound 2

In the N₂ gas purging system, compound “e” (1.0 equivalent) wasdissolved in toluene solvent, and compound “g” (1.2 equivalent) wasadded. K₂CO₃ (8.8 equivalent) was dissolved in distilled water and addedinto the solution. Tetrahydrofuran solvent was added, and palladium (0.1equivalent) was added. The mixture was refluxed and stirred under atemperature of 80° C. After completion of the reaction, the mixture wasextracted by using sodium hydroxide aqueous solution and toluene.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and the remaining organic solvent was removed. The resultantwas wet-refined by column-chromatography using hexane andre-crystallized such that compound 2 was obtained. (yield: 56%)

3. Synthesis of Compound 3

(1) Compound “h”

In the N₂ gas purging system, 4-phenylbromosulfone (1.0 equivalent) wasdissolved in toluene solvent, and phenylboronic acid (0.9 equivalent)was added. K₂CO₃ (4 equivalent) was dissolved in distilled water andadded into the solution. Tetrahydrofuran solvent was added, andpalladium (0.05 equivalent) was added. The mixture was refluxed andstirred under a temperature of 80° C. After completion of the reaction,the mixture was extracted by using ethylacetate and distilled water.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and remaining organic solvent was removed. The resultant waswet-refined by column-chromatography using ethylacetate and hexane suchthat compound “h” of solid was obtained. (yield: 75%)

(2) Compound 3

In the N₂ gas purging system, compound “h” (1.0 equivalent), compound“d” (1.1 equivalent), Pd(OAc)₂ (0.019 equivalent), P(t-Bu)₃ (50 wt %,0.046 equivalent), and sodium tert-butoxide (1.9 equivalent) were addedinto toluene solvent and stirred. The solution was refluxed and stirredfor 12 hours under a temperature of 120° C. After completion of thereaction, the solution was cooled in room temperature and extracted bywater and ethylacetate. Moisture was removed from the extracted organiclayer by using magnesium sulfate, and the solvent was removed. Theresultant was wet-refined by column-chromatography using hexane andethylacetate such that compound 3 was obtained. (yield: 65%)

4. Synthesis of Compound 4

In the N₂ gas purging system, compound “h” (1.0 equivalent) wasdissolved in toluene solvent, and compound “g” (1.2 equivalent) wasadded. K₂CO₃ (8.8 equivalent) was dissolved in distilled water and addedinto the solution. Tetrahydrofuran solvent was added, and palladium (0.1equivalent) was added. The mixture was refluxed and stirred under atemperature of 80° C. After completion of the reaction, the mixture wasextracted by using sodium hydroxide aqueous solution and toluene.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and remained organic solvent was removed. The resultant waswet-refined by column-chromatography using hexane and re-crystallizedsuch that compound 4 was obtained. (yield: 60%)

5. Synthesis of Compound 5

In the N₂ gas purging system, Pd(dba)₂ (5 mol %) as catalyst andP(t-Bu)₃ (4 mol %) was added into toluene solvent and stirred for about15 minutes. 2-chloro-4,6-diphenyl-1,3,5-triazine (33.8 mmol), compound“d” (33.8 mmol), and NaOt-Bu (60.6 mmol) were additionally added, andthe mixture was stirred for 5 hours under a temperature of 90° C. Aftercompletion of the reaction, the mixture was filtered by celite, and thesolvent was removed. The filtered solid was refined bycolumn-chromatography using hexane and dichloromethane andre-crystallized using hexane such that compound 5 was obtained. (yield:59%)

6. Synthesis of Compound 6

In the N₂ gas purging system, 2-chloro-4,6-diphenyl-1,3,5-triazine (1.0equivalent), compound “g” (1.1 equivalent), Na₂CO₃ (5 equivalent), andNH₄Cl were added into toluene/distilled water (1:1) solvent and stirred.In the N₂ gas condition, the solution was stirred for 30 minutes, andtetrakis(triphenylphosphine)Pd(0) (0.05 equivalent) was added. Thesolution was stirred for 10 minutes and was additionally stirred for 16hours under a temperature of 100° C. After completion of the reaction,the solution was cooled in room temperature and extracted bydichloromethane. Moisture was removed from the extracted organic layerby using magnesium sulfate, and remaining organic solvent was removed.The resultant was wet-refined by column-chromatography usingdichloromethane and hexane and re-crystallized by chloroform such thatcompound 6 of solid was obtained. (yield: 70%)

7. Synthesis of Compound 7

(1) Compound “i”

In the N₂ gas purging system, copper iodide (0.1 equivalent) and1,10-phenanthroline (0.2 equivalent) were added into dimethylformamide(DMF) solvent, and 4-azabenzimidazole, 1-bromo-4-iodobenzene (1.2equivalent), and cesium carbonate (2 equivalent) were additionallyadded. The solution was refluxed and stirred for 16 hours under atemperature of 110° C. After completion of the reaction, DMF solvent wasremoved, and the resultant was extracted by dichloromethane. Moisturewas removed from the extracted organic layer by using magnesium sulfate,and the solvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate andre-crystallization using dichloromethane such that compound “i” wasobtained. (yield: 78%)

(2) Compound 7

In the N₂ gas purging system, compound “i” (1.0 equivalent), compound“d” (1.1 equivalent), Pd(OAc)₂ (0.019 equivalent), P(t-Bu)₃ (50 wt %,0.046 equivalent) and sodium tert-butoxide (1.9 equivalent) were addedinto toluene solvent and stirred. The solution was refluxed and stirredfor 12 hours under a temperature of 120° C. After completion of thereaction, the solution was cooled in room temperature and extracted bywater and ethylacetate. Moisture was removed from the extracted organiclayer by using magnesium sulfate, and the solvent was removed. Theresultant was wet-refined by column-chromatography using hexane andethylacetate such that compound 7 was obtained. (yield: 60%)

8. Synthesis of Compound 8

(1) Compound “j”

In the N₂ gas purging system, copper iodide (0.1 equivalent) and1,10-phenanthroline (0.2 equivalent) were added into dimethylformamide(DMF) solvent, and 4-azabenzimidazole,1-bromo-3,5-dimethyl-4-iodobenzene (1.3 equivalent), and cesiumcarbonate (2 equivalent) were additionally added. The solution wasrefluxed and stirred for 16 hours under a temperature of 110° C. Aftercompletion of the reaction, DMF solvent was removed, and the resultantwas extracted by dichloromethane. Moisture was removed from theextracted organic layer by using magnesium sulfate, and the solvent wasremoved. The resultant was wet-refined by column-chromatography usinghexane and ethylacetate and re-crystallization using dichloromethanesuch that compound “j” was obtained. (yield: 60%)

(2) Compound 8

In the N₂ gas purging system, compound “j” (1.0 equivalent), compound“d” (1.1 equivalent), Pd(OAc)₂ (0.019 equivalent), P(t-Bu)₃ (50 wt %,0.046 equivalent), and sodium tert-butoxide (1.9 equivalent) were addedinto toluene solvent and stirred. The solution was refluxed and stirredfor 12 hours under a temperature of 120° C. After completion of thereaction, the solution was cooled in room temperature and extracted bywater and ethylacetate. Moisture was removed from the extracted organiclayer by using magnesium sulfate, and the solvent was removed. Theresultant was wet-refined by column-chromatography using hexane andethylacetate such that compound 8 was obtained. (yield: 50%)

9. Synthesis of Compound 9

(1) Compound “k”

In the N₂ gas purging system, copper iodide (0.1 equivalent) and1,10-phenanthroline (0.2 equivalent) were added into dimethylformamide(DMF) solvent, and benzimidazole, 1-bromo-4-iodobenzene (1.2 equivalent)and cesium carbonate (2 equivalent) were additionally added. Thesolution was refluxed and stirred for 16 hours under a temperature of110° C. After completion of the reaction, DMF solvent was removed, andthe resultant was extracted by dichloromethane. Moisture was removedfrom the extracted organic layer by using magnesium sulfate, and thesolvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate andre-crystallization using dichloromethane such that compound “k” wasobtained. (yield: 80%)

(2) Compound 9

In the N₂ gas purging system, compound “k” (1.0 equivalent), compound“d” (1.1 equivalent), Pd(OAc)₂ (0.019 equivalent), P(t-Bu)₃ (50 wt %,0.046 equivalent), and sodium tert-butoxide (1.9 equivalent) were addedinto toluene solvent and stirred. The solution was refluxed and stirredfor 12 hours under a temperature of 120° C. After completion of thereaction, the solution was cooled into the room temperature andextracted by water and ethylacetate. Moisture was removed from theextracted organic layer by using magnesium sulfate, and the solvent wasremoved. The resultant was wet-refined by column-chromatography usinghexane and ethylacetate such that compound 9 was obtained. (yield: 62%)

10. Synthesis of Compound 10

(1) Compound “l”

In the N₂ gas purging system, copper iodide (0.1 equivalent) and1,10-phenanthroline (0.2 equivalent) were added into dimethylformamide(DMF) solvent, and benzimidazole, 1-bromo-3,5-dimethyl-4-iodobenzene(1.3 equivalent) and cesium carbonate (2 equivalent) were additionallyadded. The solution was refluxed and stirred for 16 hours under atemperature of 110° C. After completion of the reaction, DMF solvent wasremoved, and the resultant was extracted by dichloromethane. Moisturewas removed from the extracted organic layer by using magnesium sulfate,and the solvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate andre-crystallization using dichloromethane such that compound “l” wasobtained. (yield: 58%)

(2) compound 10

In the N₂ gas purging system, compound “l” (1.0 equivalent), compound“d” (1.1 equivalent), Pd(OAc)₂ (0.019 equivalent), P(t-Bu)₃ (50 wt %,0.046 equivalent), and sodium tert-butoxide (1.9 equivalent) were addedinto toluene solvent and stirred. The solution was refluxed and stirredfor 12 hours under a temperature of 120° C. After completion of thereaction, the solution was cooled in room temperature and extracted bywater and ethylacetate. Moisture was removed from the extracted organiclayer by using magnesium sulfate, and the solvent was removed. Theresultant was wet-refined by column-chromatography using hexane andethylacetate such that compound 10 was obtained. (yield: 46%)

11. Synthesis of Compound 11

(1) Compound “a”

In the N₂ gas purging system, N-phenylanthranilic acid (46.9 mmol) wasadded into methanol solvent and stirred. The mixture was additionallystirred for 10 minutes under a temperature of 0° C., and thionylchloride (21.2 mmol) was slowly dropped. The mixed solution was stirredfor 12 hours or more under a temperature of 90° C. After completion ofthe reaction, the solvent was removed, and the mixed solution wasextracted by distilled water and ethylacetate. Moisture was removed fromthe extracted organic layer by using magnesium sulfate, and the solventwas removed. The resultant was wet-refined by column-chromatographyusing hexane and ethylacetate such that compound “a” of dark yellowliquid was obtained. (yield: 81%)

(2) Compound “b”

In the N₂ gas purging system, compound “a” (38.1 mmol) andtetrahydrofuran solvent was stirred. Methyl magnesium bromide (4.6equivalent) was slowly dropped in the solution, and the solution wasstirred and reacted for 12 hours or more under room temperature. Aftercompletion of the reaction, distilled water was slowly added, and thesolution was extracted by ethylacetate. Moisture was removed from theextracted organic layer by using magnesium sulfate, and the solvent wasremoved. The resultant was wet-refined by column-chromatography usinghexane and ethylacetate such that compound “b” of yellow liquid wasobtained. (yield: 87%)

(3) Compound “c”

In the N₂ gas purging system, compound “b” (33.1 mmol) was put intoexcess phosphoric acid solvent (160 ml), and the solution was stirredunder room temperature. The solution was additionally stirred for 16hour or more, and distilled water (200 to 250 ml) was slowly added. Thesolution was stirred for 0.5 to 1 hour, and the precipitated solid wasfiltered. The filtered solid was extracted by using sodium hydroxideaqueous solution and dichloromethane solvent. Moisture was removed fromthe extracted organic layer by using magnesium sulfate, and the organicsolvent was removed such that compound “c” of white solid was obtained.(yield: 69%)

(4) Compound “d”

In the N₂ gas purging system, compound “c” (23.9 mmol),1,4-dibromobenzene (35.8 mmol), palladium(II)acetate (2 mol %),tri-tert-butylphosphate (5 mol %) and sodium-tert-butoxide (2.03equivalent) was added into toluene solvent and stirred. The mixedsolution was refluxed and stirred for 12 hours. After completion of thereaction, the solution was extracted by using distilled water andethylacetate. Moisture was removed from the extracted organic layer byusing magnesium sulfate, and the solvent was removed. The resultant waswet-refined by column-chromatography using hexane and ethylacetate suchthat compound “d” was obtained. (yield: 81%)

(5) Compound “e”

In the N₂ gas purging system, compound “d”, bis(pinacolate)diboron (1.2equivalent), [1,1-bis(diphenylphosphineo)ferrocene]palladium(II),dichloride dichloromethane, 1,1-bis(diphenylphosphino)ferrocene, andpotassium acetate were added into 1,4-dioxane/toluene (1:1) solvent inthe light-shielded flask and stirred. After bubbles were disappeared,the solution was stirred for 17 hours under a temperature of 120° C.After completion of the reaction, the solution was cooled into the roomtemperature, and the solvent was removed. The resultant was washed bytoluene and refined such that compound “e” was obtained. (yield: 90%)

(6) Compound “f”

In the N₂ gas purging system, 2,8-dibromodibenzothiophene (14.6 mmol)and acetic acid solvent were mixed and stirred. Hydrogen peroxide (64.8mmol) was added and stirred in room temperature for about 30 minutes,and the mixture were refluxed and stirred for 12 hours or more. Aftercompletion of the reaction, distilled water (50 ml) was added andstirred to wash. After filtering the mixture, the solids was mixed withexcess hydrogen peroxide and stirred to wash for 30 to 60 minutes. Thesolids was washed by distilled water and filtered and dried such thatcompound “f” in white solid was obtained. (yield: 90%)

(7) Compound 11

In the N₂ gas purging system, compound “f” (1.0 equivalent) wasdissolved in toluene solvent, and compound “e” (2.4 equivalent) wasadded. K₂CO₃ (8.8 equivalent) was dissolved in distilled water and addedinto the solution. Tetrahydrofuran solvent was added, and palladium (0.1equivalent) was added. The mixture was refluxed and stirred under atemperature of 80° C. After completion of the reaction, the mixture wasextracted by using sodium hydroxide aqueous solution and toluene.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and remained organic solvent was removed. The resultant waswet-refined by column-chromatography using hexane and re-crystallizedsuch that compound 11 was obtained. (yield: 85%)

12. Synthesis of Compound 12

(1) Compound “g”

In the N₂ gas purging system, carbazole (29.9 mmol), 1,4-dibromobenzene(44.9 mmol), palladium(II)acetate (2 mol %), tri-tert-butylphosphate (5mol %) and sodium-tert-butoxide (2.03 equivalent) was added into toluenesolvent and stirred. The mixed solution was refluxed and stirred for 12hours. After completion of the reaction, the solution was extracted byusing distilled water and ethylacetate. Moisture was removed from theextracted organic layer by using magnesium sulfate, and the solvent wasremoved. The resultant was wet-refined by column-chromatography usinghexane and ethylacetate such that compound “g” was obtained. (yield:80%)

(2) Compound “h”

In the N₂ gas purging system, compound “g” was dissolved intetrahydrofuran and stirred. n-butyl-lithium (26.9 mmol) was slowlyadded into the solution under a temperature of −78° C., and the mixedsolution was stirred for 1 hour. With maintaining the low temperaturecondition, tri-ethylborate (21.6 mmol) was added, and the mixed solutionwas stirred under room temperature. The mixed solution was stirred for12 hours under room temperature, and the reaction was completed.Distilled water was slowly added, and a mixed solution of distilledwater/hydrochloric acid (8:2) was added to be pH 2. The solution wasextracted using distilled water and ethylacetate. Moisture was removedfrom the extracted organic layer by using magnesium sulfate, and thesolvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate such that compound“h” was obtained. (yield: 87%)

(3) Compound “i”

In the N₂ gas purging system, compound “f” (1.0 equivalent) wasdissolved in toluene solvent, and compound “h” (0.9 equivalent) wasadded. K₂CO₃ (4 equivalent) was dissolved in distilled water and addedinto the solution. Tetrahydrofuran solvent was added, and palladium(0.05 equivalent) was added. The mixture was refluxed and stirred undera temperature of 80° C. After completion of the reaction, the mixturewas extracted by using ethylacetate and distilled water. Moisture wasremoved from the extracted organic layer by using magnesium sulfate, andremaining organic solvent was removed. The resultant was wet-refined bycolumn-chromatography using ethylacetate and hexane such that compound“i” of solid was obtained. (yield: 65%)

(4) Compound 12

In the N₂ gas purging system, compound “i” (1.0 equivalent) wasdissolved in toluene solvent, and compound “e” (1.2 equivalent) wasadded. K₂CO₃ (8.8 equivalent) was dissolved in distilled water and addedinto the solution. Tetrahydrofuran solvent was added, and palladium (0.1equivalent) was added. The mixture was refluxed and stirred under atemperature of 80° C. After completion of the reaction, the mixture wasextracted by using sodium hydroxide aqueous solution and toluene.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and remained organic solvent was removed. The resultant waswet-refined by column-chromatography using hexane and re-crystallizedsuch that compound 12 was obtained. (yield: 75%)

13. Synthesis of Compound 13

In the N₂ gas purging system, 4-bromophenylsulfone (1.0 equivalent) wasdissolved in toluene solvent, and compound “e” (2.4 equivalent) wasadded. K₂CO₃ (8.8 equivalent) was dissolved in distilled water and addedinto the solution. Tetrahydrofuran solvent was added, and palladium (0.1equivalent) was added. The mixture was refluxed and stirred under atemperature of 80° C. After completion of the reaction, the mixture wasextracted by using sodium hydroxide aqueous solution and toluene.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and remained organic solvent was removed. The resultant waswet-refined by column-chromatography using hexane and re-crystallizedsuch that compound 13 was obtained. (yield: 78%)

14. Synthesis of Compound 14

(1) Compound “j”

In the N₂ gas purging system, 4-bromophenylsulfone (1.0 equivalent) wasdissolved in toluene solvent, and compound “h” (0.9 equivalent) wasadded. K₂CO₃ (4 equivalent) was dissolved in distilled water and addedinto the solution. Tetrahydrofuran solvent was added, and palladium(0.05 equivalent) was added. The mixture was refluxed and stirred undera temperature of 80° C. After completion of the reaction, the mixturewas extracted by using ethylacetate and distilled water. Moisture wasremoved from the extracted organic layer by using magnesium sulfate, andremained organic solvent was removed. The resultant was wet-refined bycolumn-chromatography using ethylacetate and hexane such that compound“j” of solid was obtained. (yield: 60%)

(2) Compound 14

In the N₂ gas purging system, compound “j” (1.0 equivalent) wasdissolved in toluene solvent, and compound “e” (1.2 equivalent) wasadded. K₂CO₃ (8.8 equivalent) was dissolved in distilled water and addedinto the solution. Tetrahydrofuran solvent was added, and palladium (0.1equivalent) was added. The mixture was refluxed and stirred under atemperature of 80° C. After completion of the reaction, the mixture wasextracted by using sodium hydroxide aqueous solution and toluene.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and remaining organic solvent was removed. The resultant waswet-refined by column-chromatography using hexane and re-crystallizedsuch that compound 14 was obtained. (yield: 55%)

15. Synthesis of Compound 15

(1) Compound “k”

In the light-shielded flask of the N₂ gas purging system, bromobenzene(0.9 equivalent) was dissolved in tetrahydrofuran under a temperature of−78° C., and n-butyl-lithium was slowly dropped.2,4,6-trichloro-1,3,5-triazine dissolved in tetrahydrofuran was droppedinto the solution using cannula in the N₂ condition and was stirred for8 hours. After completion of the reaction, the resultant was refinedsuch that compound “k” was obtained. (yield: 45%)

(2) Compound 15

In the N₂ gas purging system, compound “k” (1.0 equivalent), compound“e” (2.1 equivalent), Na₂CO₃ (5 equivalent) and NH₄Cl (0.2 equivalent)were added into solvent of toluene/distilled water (1:1) and stirred.The solution was stirred for 30 minutes in the N₂ condition,tetrakis(triphenylphosphine)palladium(0) (0.05 equivalent) wasadditionally added and stirred for 10 minutes. The mixture was stirredfor 16 hours under a temperature of 100° C. After completion of thereaction, the solution was cooled in room temperature and extracted bydichloromethane and distilled water. Moisture was removed from theextracted organic layer by using magnesium sulfate, and the solvent wasremoved. The resultant was wet-refined by column-chromatography usingdichloromethane and hexane and re-crystallized by using chloroform andacetonitrile such that compound 15 was obtained. (yield: 75%)

16. Synthesis of Compound 16

(1) Compound “l”

In the N₂ gas purging system, compound “k” (1.0 equivalent), compound“h” (0.9 equivalent) and Na₂CO₃ (0.6 equivalent) were put into solventof toluene/dioxane/distilled water (1:1:0.7) and stirred. Pd(PPh₃)₄(tetrakis(triphenylphosphine)palladium(0), 0.3 equivalent) wasadditionally added and stirred for 16 hours. After completion of thereaction, the solution was cooled in room temperature. The organic layerwas washed and filtered by distilled water in silica-gel. The solventand distilled water were removed, and the resultant was re-crystallizedby chloroform and dried such that compound “l” was obtained. (yield:80%)

(2) Compound 16

In the N₂ gas purging system, compound “l” (1.0 equivalent), compound“e” (1.05 equivalent), Na₂CO₃ (5 equivalent) and NH₄Cl (0.2 equivalent)were added into solvent of toluene/distilled water (1:1) and stirred.The solution was stirred for 30 minutes in the N₂ condition,tetrakis(triphenylphosphine)palladium(0) (0.05 equivalent) wasadditionally added and stirred for 10 minutes. The mixture was stirredfor 16 hours under a temperature of 100° C. After completion of thereaction, the solution was cooled into the room temperature andextracted by dichloromethane and distilled water. Moisture was removedfrom the extracted organic layer by using magnesium sulfate, and thesolvent was removed. The resultant was wet-refined bycolumn-chromatography using dichloromethane and hexane andre-crystallized by using chloroform and acetonitrile such that compound16 was obtained. (yield: 60%)

17. Synthesis of Compound 17

(1) Compound “m”

In the N₂ gas purging system, 2,3-hydroquinoxaline (3 g) was put intoPBr₅ solvent and stirred for 4 hours under a temperature of 160° C.After completion of the reaction, the solution was cooled into 0° C. andstirred for 30 minutes. The mixture was extracted by dichloromethane anddistilled water and washed by 1N sodium hydroxide. Moisture was removedby using magnesium sulfate, and the resultant was enriched such thatcompound “m” was obtained. (yield: 96%)

(2) Compound 17

Compound “m” (1.0 equivalent), compound “e” (3 equivalent), Pd₂(dba)₃(0.1 equivalent), tri-cyclohexylphosphine (0.1 equivalent) and 1.35MK₃PO₄ aqueous solution were put into dioxane solvent and stirred. In theN₂ gas purging system, the mixture was refluxed and stirred for 48hours. After completion of the reaction, the solution was cooled intothe room temperature and extracted by dichloromethane and distilledwater. Moisture was removed from the extracted organic layer by usingmagnesium sulfate, and the solvent was removed. The resultant waswet-refined by column-chromatography using dichloromethane and hexaneand re-crystallization such that compound 17 was obtained. (yield: 36%)

18. Synthesis of Compound 18

(1) Compound “n”

In the N₂ gas purging system, compound “m” (1.0 equivalent) wasdissolved in toluene solvent, and compound “h” (0.9 equivalent) wasadded into the solution. K₂CO₃ (4 equivalent) was dissolved in distilledwater and added into the mixed solution. Tetrahydrofuran solvent wasadded, and palladium (0.05 equivalent) was added. The mixture wasrefluxed and stirred under a temperature of 80° C. After completion ofthe reaction, the mixture was extracted by using ethylacetate solventand distilled water, and moisture was removed from the extracted organiclayer by using magnesium sulfate. Remaining organic solvent was removed,and the resultant was wet-refined by column-chromatography usingethylacetate and hexane such that compound “n” of solid was obtained.(yield: 55%)

(2) Compound 18

In the N₂ gas purging system, compound “n” (1.0 equivalent) wasdissolved in toluene solvent, and compound “e” (1.2 equivalent) wasadded into the solution. K₂CO₃ (8.8 equivalent) was dissolved indistilled water and added into the mixed solution. Tetrahydrofuransolvent was added, and palladium (0.1 equivalent) was added. The mixturewas refluxed and stirred under a temperature of 80° C. After completionof the reaction, the mixture was extracted by using sodium hydroxideaqueous solution and toluene. Moisture was removed from the extractedorganic layer by using magnesium sulfate, and remained organic solventwas removed. The resultant was wet-refined by column-chromatographyusing hexane and re-crystallized such that compound 18 was obtained.(yield: 45%)

19. Synthesis of Compound 19

(1) Compound “a”

In the N₂ gas purging system, 2,8-dibromodibenzothiophene (14.6 mmol)and acetic acid solvent were mixed and stirred. Hydrogen peroxide (64.8mmol) was added and stirred in the room temperature for about 30minutes, and the mixture were refluxed and stirred for 12 hours or more.After completion of the reaction, distilled water (50 ml) was added andstirred to wash. After filtering the mixture, the solids was mixed withexcess hydrogen peroxide and stirred to wash for 30 to 60 minutes. Thesolids was washed by distilled water and filtered and dried such thatcompound “a” in white solid was obtained. (yield: 90%)

(2) Compound “b”

In the N₂ gas purging system, N-phenylanthranilic acid (46.9 mmol) andmethanol solvent were mixed and stirred. The mixture was additionallystirred for 10 minutes under a temperature of 0° C., and thionylchloride (21.2 mmol) was slowly dropped. The mixed solution was stirredfor 12 hours or more under a temperature of 90° C. After completion ofthe reaction, the solvent was removed, and the mixed solution wasextracted by distilled water and ethylacetate. Moisture was removed fromthe extracted organic layer by using magnesium sulfate, and the solventwas removed. The resultant was wet-refined by column-chromatographyusing hexane and ethylacetate such that compound “b” of dark yellowliquid was obtained. (yield: 81%)

(3) Compound “c”

In the N₂ gas purging system, compound “b” (38.1 mmol) andtetrahydrofuran solvent was stirred. Methyl magnesium bromide (4.6equivalent) was slowly dropped in the solution, and the solution wasstirred and reacted for 12 hours or more under room temperature. Aftercompletion of the reaction, distilled water was slowly added, and thesolution was extracted by ethylacetate. Moisture was removed from theextracted organic layer by using magnesium sulfate, and the solvent wasremoved. The resultant was wet-refined by column-chromatography usinghexane and ethylacetate such that compound “c” of yellow liquid wasobtained. (yield: 87%)

(4) Compound “d”

In the N₂ gas purging system, compound “c” (33.1 mmol) was put intoexcess phosphoric acid solvent (160 ml), and the solution was stirredunder room temperature. The solution was additionally stirred for 16hours or more, and distilled water (200 to 250 ml) was slowly added. Thesolution was stirred for 0.5 to 1 hour, and the precipitated solid wasfiltered. The filtered solid was extracted by using sodium hydroxideaqueous solution and dichloromethane solvent. Moisture was removed fromthe extracted organic layer by using magnesium sulfate, and the organicsolvent was removed such that compound “d” of white solid was obtained.(yield: 69%)

(5) Compound 19

In the N₂ gas purging system, compound “d” (0.3 mol), compound “a” (0.15mol), Pd(OAc)₂ (6.11 mmol), P(t-Bu)₃ (50 wt %, 15.28 mmol), and sodiumtert-butoxide (0.61 mol) were added into toluene solvent and stirred.The solution was refluxed and stirred for 12 hours under a temperatureof 120° C. After completion of the reaction, the solution was cooled inroom temperature and extracted by water and ethylacetate. Moisture wasremoved from the extracted organic layer by using magnesium sulfate, andthe solvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate such that compound19 was obtained. (yield: 81%)

20. Synthesis of Compound 20

In the N₂ gas purging system, compound “d” (0.3 mol),4-bromophenylsulfone (0.15 mol), Pd(OAc)₂ (6.11 mmol), P(t-Bu)₃ (50 wt%, 15.28 mmol), and sodium tert-butoxide (0.61 mol) were added intotoluene solvent and stirred. The solution was refluxed and stirred for12 hours under a temperature of 120° C. After completion of thereaction, the solution was cooled into the room temperature andextracted by water and ethylacetate. Moisture was removed from theextracted organic layer by using magnesium sulfate, and the solvent wasremoved. The resultant was wet-refined by column-chromatography usinghexane and ethylacetate such that compound 20 was obtained. (yield: 80%)

21. Synthesis of Compound 21

(1) Compound “e”

In the light-shielded flask of the N₂ gas purging system, bromobenzene(0.9 equivalent) was dissolved in tetrahydrofuran under a temperature of−78° C., and n-butyl-lithium was slowly dropped.2,4,6-trichloro-1,3,5-triazine dissolved in tetrahydrofuran was droppedinto the solution using cannula in the N₂ condition and was stirred for8 hours. After completion of the reaction, the resultant was refinedsuch that compound “e” was obtained. (yield: 45%)

(2) Compound 21

In the N₂ gas purging system, Pd(dba)₂ (5 mol %) as catalyst andP(t-Bu)₃ (4 mol %) was added into toluene solvent and stirred for about15 minutes. Compound 2 (33.8 mmol), compound “d” (16.9 mmol), andNaOt-Bu (60.6 mmol) were additionally added, and the mixture was stirredfor 5 hours under a temperature of 90° C. After completion of thereaction, the mixture was filtered by celite, and the solvent wasremoved. The filtered solid was refined by column-chromatography usinghexane and dichloromethane and re-crystallized using hexane such thatcompound 21 was obtained. (yield: 59%)

22. Synthesis of Compound 22

In the N₂ gas purging system, compound “d” (0.3 mol),5,8-dibromo-quinoxaline (0.15 mol), Pd(OAc)₂ (6.11 mmol), P(t-Bu)₃ (50wt %, 15.28 mmol), and sodium tert-butoxide (0.61 mol) were added intotoluene solvent and stirred. The solution was refluxed and stirred for12 hours under a temperature of 120° C. After completion of thereaction, the solution was cooled in room temperature and extracted bywater and ethylacetate. Moisture was removed from the extracted organiclayer by using magnesium sulfate, and the solvent was removed. Theresultant was wet-refined by column-chromatography using hexane andethylacetate such that compound 22 was obtained. (yield: 79%)

23. Synthesis of Compound 23

(1) Compound “f”

In the N₂ gas purging system, 3,4-diaminothiophene dihydrochloride (5.52mmol) was slowly added into a mixed solution of Na₂CO₃ (5%, 60 ml) andglyoxal (6.1 mmol) for approximately 5 minutes. Diluted glyoxal solution(40%, 15 mol) was additionally added. The mixture was stirred for 3hours under room temperature and quickly extracted by ethylacetate.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and the solvent was removed without heating. The resultant waswet-refined by column-chromatography using dichloromethane and hexanesuch that compound “f” was obtained. (yield: 70%)

(2) Compound “g”

In the N₂ gas purging system, compound “f” (14.7 mmol) was added intosolvent of chloroform/acetic acid (1:1) and stirred. The solution wascooled into 0° C., and N-Bromsuccinimid (NBS, 32.3 mmol) wasadditionally added. The mixture was stirred for 12 hours under roomtemperature. After completion of the reaction, distilled water of anamount as much as the reaction solvent was added into the mixture, andthe solution was extracted by chloroform. Moisture was removed from theextracted organic layer by using magnesium sulfate, and the solvent wasremoved without heating. The solids were washed by diethyl ether. Theresultant was wet-refined by column-chromatography using dichloromethaneand hexane such that compound “g” was obtained. (yield: 75%)

(3) Compound 23

In the N₂ gas purging system, compound “d” (0.3 mol), compound “g” (0.15mol), Pd(OAc)₂ (6.11 mmol), P(t-Bu)₃ (50 wt %, 15.28 mmol), and sodiumtert-butoxide (0.61 mol) were added into toluene solvent and stirred.The solution was refluxed and stirred for 12 hours under a temperatureof 120° C. After completion of the reaction, the solution was cooled inroom temperature and extracted by water and ethylacetate. Moisture wasremoved from the extracted organic layer by using magnesium sulfate, andthe solvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate such that compound23 was obtained. (yield: 70%)

24. Synthesis of Compound 24

(1) Compound “h”

In the N₂ gas purging system, carbazole (1.0 equivalent) was dissolvedin 1,4-dioxane solvent, and CuI (0.2 equivalent) and K₃PO₄ (1.0equivalent) were added. Compound “a” (1.1 equivalent) andtrans-1,2-diaminocyclohexane were additionally added. The solution wasrefluxed and stirred for 24 hours under a temperature of 110° C. Aftercompletion of the reaction, the solution was cooled in room temperatureand extracted by ethylacetate and distilled water. Moisture was removedfrom the extracted organic layer by using magnesium sulfate, andremaining organic solvent was removed. The resultant was wet-refined bycolumn-chromatography using ethylacetate and hexane such that compound“h” was obtained. (yield: 58%)

(2) Compound 24

In the N₂ gas purging system, compound “d” (0.33 mol), compound “h”(0.33 mol), Pd(OAc)₂ (6.11 mmol), P(t-Bu)₃ (50 wt %, 15.28 mmol), andsodium tert-butoxide (0.61 mol) were added into toluene solvent andstirred. The solution was refluxed and stirred for 12 hours under atemperature of 120° C. After completion of the reaction, the solutionwas cooled in room temperature and extracted by water and ethylacetate.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and the solvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate such that compound24 was obtained. (yield: 55%)

25. Synthesis of Compound 25

(1) Compound “i”

In the N₂ gas purging system, carbazole (1.0 equivalent) was dissolvedin 1,4-dioxane solvent, and CuI (0.2 equivalent) and K₃PO₄ (1.0equivalent) were added. 4-bromophenylsulfone (1.1 equivalent) andtrans-1,2-diaminocyclohexane were additionally added. The solution wasrefluxed and stirred for 24 hours under a temperature of 110° C. Aftercompletion of the reaction, the solution was cooled in room temperatureand extracted by ethylacetate and distilled water. Moisture was removedfrom the extracted organic layer by using magnesium sulfate, andremaining organic solvent was removed. The resultant was wet-refined bycolumn-chromatography using ethylacetate and hexane such that compound“i” was obtained. (yield: 60%)

(2) Compound 25

In the N₂ gas purging system, compound “d” (0.33 mol), compound “i”(0.33 mol), Pd(OAc)₂ (6.11 mmol), P(t-Bu)₃ (50 wt %, 15.28 mmol), andsodium tert-butoxide (0.61 mol) were added into toluene solvent andstirred. The solution was refluxed and stirred for 12 hours under atemperature of 120° C. After completion of the reaction, the solutionwas cooled in room temperature and extracted by water and ethylacetate.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and the solvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate such that compound25 was obtained. (yield: 65%)

26. Synthesis of Compound 26

(1) Compound “j”

In the N₂ gas purging system, compound “a” (1.0 equivalent) wasdissolved in toluene solvent, and 4-(diphenylamino)phenylboronic acid(1.1 equivalent) was added. K₂CO₃ (4.4 equivalent) was dissolved indistilled water and added into the mixed solution. Tetrahydrofuransolvent was added, and palladium (0.05 equivalent) was added. Themixture was refluxed and stirred under a temperature of 80° C. Aftercompletion of the reaction, the mixture was extracted by usingethylacetate solvent and distilled water. Moisture was removed from theextracted organic layer by using magnesium sulfate, and remained organicsolvent was removed. The resultant was wet-refined bycolumn-chromatography using dichloromethane and hexane such thatcompound “j” was obtained. (yield: 56%)

(2) Compound 26

In the N₂ gas purging system, compound “d” (0.33 mol), compound 1″ (0.33mol), Pd(OAc)₂ (6.11 mmol), P(t-Bu)₃ (50 wt %, 15.28 mmol), and sodiumtert-butoxide (0.61 mol) were added into toluene solvent and stirred.The solution was refluxed and stirred for 12 hours under a temperatureof 120° C. After completion of the reaction, the solution was cooled inroom temperature and extracted by water and ethylacetate. Moisture wasremoved from the extracted organic layer by using magnesium sulfate, andthe solvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate such that compound26 was obtained. (yield: 50%)

27. Synthesis of Compound 27

(1) Compound “k”

In the N₂ gas purging system, 4-bromophenylsulfone (1.0 equivalent) wasdissolved in toluene solvent, and 4-(diphenylamino)phenylboronic acid(1.1 equivalent) was added. K₂CO₃ (4.4 equivalent) was dissolved indistilled water and added into the mixed solution. Tetrahydrofuransolvent was added, and palladium (0.05 equivalent) was added. Themixture was refluxed and stirred under a temperature of 80° C. Aftercompletion of the reaction, the mixture was extracted by ethylacetate.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and remaining organic solvent was removed. The resultant waswet-refined by column-chromatography using dichloromethane and hexanesuch that compound “k” was obtained. (yield: 55%)

(2) Compound 27

In the N₂ gas purging system, compound “d” (0.33 mol), compound “k”(0.33 mol), Pd(OAc)₂ (6.11 mmol), P(t-Bu)₃ (50 wt %, 15.28 mmol), andsodium tert-butoxide (0.61 mol) were added into toluene solvent andstirred. The solution was refluxed and stirred for 12 hours under atemperature of 120° C. After completion of the reaction, the solutionwas cooled in room temperature and extracted by water and ethylacetate.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and the solvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate such that compound27 was obtained. (yield: 45%)

28. Synthesis of Compound 28

(1) Compound “l”

In the N₂ gas purging system, carbazole (1.0 equivalent) was dissolvedin 1,4-dioxane solvent, and CuI (0.2 equivalent) and K₃PO₄ (1.0equivalent) were added. 5,8-dibromoquinoxalin (1.1 equivalent) andtrans-1,2-diaminocyclohexane were additionally added. The solution wasrefluxed and stirred for 24 hours under a temperature of 110° C. Aftercompletion of the reaction, the solution was cooled into the roomtemperature and extracted by ethylacetate and distilled water. Moisturewas removed from the extracted organic layer by using magnesium sulfate,and remained organic solvent was removed. The resultant was wet-refinedby column-chromatography using ethylacetate and hexane such thatcompound “l” was obtained. (yield: 48%)

(2) Compound 28

In the N₂ gas purging system, compound “d” (0.33 mol), compound “l”(0.33 mol), Pd(OAc)₂ (6.11 mmol), P(t-Bu)₃ (50 wt %, 15.28 mmol), andsodium tert-butoxide (0.61 mol) were added into toluene solvent andstirred. The solution was refluxed and stirred for 12 hours under atemperature of 120° C. After completion of the reaction, the solutionwas cooled in room temperature and extracted by water and ethylacetate.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and the solvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate such that compound28 was obtained. (yield: 50%)

29. Synthesis of Compound 29

(1) Compound “m”

In the N₂ gas purging system, 5,8-dibromoquinoxaline (1.0 equivalent)was dissolved in toluene solvent, and 4-(diphenylamino)phenylboronicacid (1.1 equivalent) was added. K₂CO₃ (4.4 equivalent) was dissolved indistilled water and added into the mixed solution. Tetrahydrofuransolvent was added, and palladium (0.05 equivalent) was added. Themixture was refluxed and stirred under a temperature of 80° C. Aftercompletion of the reaction, the mixture was extracted by ethylacetate.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and remaining organic solvent was removed. The resultant waswet-refined by column-chromatography using dichloromethane and hexanesuch that compound “m” was obtained. (yield: 43%)

(2) Compound 29

In the N₂ gas purging system, compound “d” (0.33 mol), compound “m”(0.33 mol), Pd(OAc)₂ (6.11 mmol), P(t-Bu)₃ (50 wt %, 15.28 mmol), andsodium tert-butoxide (0.61 mol) were added into toluene solvent andstirred. The solution was refluxed and stirred for 12 hours under atemperature of 120° C. After completion of the reaction, the solutionwas cooled in room temperature and extracted by water and ethylacetate.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and the solvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate such that compound29 was obtained. (yield: 50%)

30. Synthesis of Compound 30

(1) Compound “n”

In the N₂ gas purging system, carbazole (1.0 equivalent) was dissolvedin 1,4-dioxane solvent, and CuI (0.2 equivalent) and K₃PO₄ (1.0equivalent) were added. Compound “g” (1.1 equivalent) andtrans-1,2-diaminocyclohexane were additionally added. The solution wasrefluxed and stirred for 24 hours under a temperature of 110° C. Aftercompletion of the reaction, the solution was cooled in room temperatureand extracted by ethylacetate and distilled water. Moisture was removedfrom the extracted organic layer by using magnesium sulfate, andremaining organic solvent was removed. The resultant was wet-refined bycolumn-chromatography using ethylacetate and hexane such that compound“n” was obtained. (yield: 45%)

(2) Compound 30

In the N₂ gas purging system, compound “d” (0.33 mol), compound “n”(0.33 mol), Pd(OAc)₂ (6.11 mmol), P(t-Bu)₃ (50 wt %, 15.28 mmol), andsodium tert-butoxide (0.61 mol) were added into toluene solvent andstirred. The solution was refluxed and stirred for 12 hours under atemperature of 120° C. After completion of the reaction, the solutionwas cooled in room temperature and extracted by water and ethylacetate.Moisture was removed from the extracted organic layer by using magnesiumsulfate, and the solvent was removed. The resultant was wet-refined bycolumn-chromatography using hexane and ethylacetate such that compound30 was obtained. (yield: 49%)

The mass spectrum data of the above compounds 1 to 30 are listed inTable 1.

TABLE 1 Calculation Found (M(H+)) Com1 C₃₃H₂₅N₁O₂S₁ 499.16 499.16 Com2C₃₉H₂₉N₁O₂S₁ 575.19 575.19 Com3 C₃₃H₂₇N₁O₂S₁ 501.18 501.18 Com4C₃₉H₃₁N₁O₂S₁ 577.21 577.21 Com5 C₃₀H₂₄N₄ 440.2 440.2 Com6 C₃₆H₂₈N₄516.23 516.23 Com7 C₂₇H₂₂N₄ 402.18 402.18 Com8 C₂₉H₂₆N₄ 430.22 430.22Com9 C₂₈H₂₃N₃ 401.19 401.19 Com10 C₃₀H₂₇N₃ 429.22 429.22 Com11C₅₄H₄₂N₂O₂S 782.30 782.30 Com12 C₅₁H₃₆N₂O₂S 740.25 740.25 Com13C₅₄H₄₂N₂O₂S 782.30 782.30 Com14 C₅₁H₃₈N₂O₂S 742.27 742.27 Com15 C₅₁H₄₁N₅723.34 723.34 Com16 C₄₈H₃₅N₅ 681.29 681.29 Com17 C₅₀H₄₀N₄ 696.33 696.33Com18 C₄₇H₃₄N₄ 654.28 654.27 Com19 C₄₂H₃₄N₂O₂S 630.23 630.23 Com20C₄₂H₃₆N₂O₂S 632.25 632.25 Com21 C₃₉H₃₃N₅ 571.27 571.27 Com22 C₃₈H₃₂N₄544.26 544.26 Com23 C₃₆H₃₀N₄S 550.22 550.22 Com24 C₃₉H₂₈N₂O₂S 588.19588.19 Com25 C₃₉H₃₀N₂O₂S 590.20 590.20 Com26 C₄₅H₃₄N₂O₂S 666.23 666.23Com27 C₄₅H₃₆N₂O₂S 668.25 668.25 Com28 C₃₅H₂₆N₄ 502.22 502.22 Com29C₄₁H₃₂N₄ 580.26 580.26 Com30 C₃₃H₂₄N₄S 508.17 508.17

The emission properties of the above compounds 3, 6, 7, 9, 11, 15, 16,23, 27, and 29 are measured and the results are listed in Table 2 andshown in FIGS. 4A to 4J. (Quantarus tau apparatus of Hamamatsu Co., Ltd.O₂ free condition.)

TABLE 2 Fluorescence Delayed fluorescence (ns) (ns)

7.28 820

9.51 5220

7.28 41100

6.32 3120

47.02 7875

23.13 3870

25.60 5755

7.66 6956

5.00 6753

3.50 5645

As shown in Table 2 and FIGS. 4A to 4J, the delayed fluorescencecompounds (Com3, Com6, Com7, Com9, Com11, Com15, Com16, Com23, Com27,and Com29) of the present disclosure show the delayed fluorescentemission of hundreds to tens of thousands of nano-seconds (ns).

As mentioned above, the delayed fluorescence compound of the presentinvention is activated by the field such that the excitons in thesinglet state “S₁” and the triplet state “T₁” are transited into theintermediated state “I₁”. As a result, both the exciton in the singletstate “S₁” and the exciton in the triplet state “T₁” are engaged in theemission.

The FADF compound is a single molecule compound having the electrondonor moiety and the electron acceptor moiety in the single moleculewith or without another electron donor moiety such that the chargetransfer is easily generated. In the FADF compound with particularconditions, the charge can be separated from the electron donor moietyto the electron acceptor moiety.

The FADF compound is activated by outer factors. It can be verified bycomparing the absorption peak and the emission peak of the solution ofthe compounds.

${\Delta \; v} = {{{vabs} - {vfl}} = {{\frac{2\Delta \; u^{2}}{{hca}^{3}}\Delta \; f} + {{constant}\mspace{14mu} \left( {{Lippert}\text{-}{Mataga}\mspace{14mu} {equation}} \right)}}}$

In the above equation, “Δυ” is the Stock-shift value, and “υabs” and“υfl” are the wave-number of the maximum absorption peak and the maximumemission peak, respectively. “h” is Planck's constant, “c” is thevelocity of light, “a” is the onsager cavity radius, and “Δμ” is adifference between the dipole moment of the excited state and the dipolemoment of the ground state. (Δμ=μ_(e)−μ_(g))

“Δf” is a value indicating the orientational polarizability of thesolvent and may be a function of the dielectric constant of the solvent(c) and the refractive index of the solvent

${\Delta \; f} = {\frac{ɛ - 1}{{2ɛ} + 1} - \frac{n^{2} - 1}{{2n^{2}} + 1}}$

Since the intensity of dipole moment in the excited state is determinedby the peripheral polarity (e.g., the polarity of the solvent), the FADFcan be verified by comparing the absorption peak and the emission peakof the solution of the compounds.

The orientational polarizability (Δf) of the mixed solvent can becalculated by using the orientational polarizability of each puresolvent and their mole fraction. When “Δf” and “Δυ” are linearly plottedby using above “Lippert-Mataga equation”, the compound may provide theFADF emission.

Namely, when the FADF complex is stabilized according to theorientational polarizability of the solvent, the emission peak isshifted in a long wavelength according to the degree of thestabilization. Accordingly, when the compound provides the FADFemission, “Δf” and “Δυ” are plotted in a linear line. When “Δf” and “Δυ”are plotted in a linear line, the compound provides the FADF emission.

In the delayed fluorescence compound of the present invention, the 25%excitons in the singlet state and the 75% excitons in the triplet stateare transited into the intermediate state by an outer force, i.e., afield generated when the OLED is driven. (Intersystem crossing.) Theexcitons in the intermediate state are transited into the ground statesuch that the emitting efficiency is improved. Namely, in thefluorescent compound, since both the singlet exciton and the tripletexciton are engaged in the emission, the emitting efficiency isimproved.

OLED

An ITO layer is deposited on a substrate and washed to form an anode (3mm*3 mm). The substrate is loaded in a vacuum chamber, and a holeinjecting layer (500 Å,NPB(N,N-di(naphthalen-1-yl)-N,N′-diphenyl-benzidine)), a holetransporting layer (100 Å, mCP(N,N′-Dicarbazolyl-3,5-benzene)), anemitting material layer (350 Å, host(bis{2-[di(phenyl)phosphino]phenyl}ether oxide) and dopant (6%)), anelectron transporting layer (300 Å,1,3,5-tri(phenyl-2-benzimidazole)-benzene), an electron injecting layer(LiF), and a cathode (Al) are sequentially formed on the anode under abase pressure of about 10⁻⁶ to 10⁻⁷ Torr.

(1) Comparative Example (Ref)

The reference compound in Formula 8 is used as the dopant to form theOLED.

(2) Example 1 (Ex1)

The compound 3 is used as the dopant to form the OLED.

(3) Example 2 (Ex2)

The compound 6 is used as the dopant to form the OLED.

(4) Example 3 (Ex3)

The compound 7 is used as the dopant to form the OLED.

(5) Example 4 (Ex4)

The compound 9 is used as the dopant to form the OLED.

(6) Example 5 (Ex5)

The compound 11 is used as the dopant to form the OLED.

(7) Example 6 (Ex6)

The compound 13 is used as the dopant to form the OLED.

(8) Example 7 (Ex7)

The compound 15 is used as the dopant to form the OLED.

(9) Example 8 (Ex8)

The compound 16 is used as the dopant to form the OLED.

(10) Example 9 (Ex9)

The compound 17 is used as the dopant to form the OLED.

(11) Example 10 (Ex10)

The compound 19 is used as the dopant to form the OLED.

(12) Example 11 (Ex11)

The compound 20 is used as the dopant to form the OLED.

(13) Example 12 (Ex12)

The compound 21 is used as the dopant to form the OLED.

(14) Example 13 (Ex13)

The compound 22 is used as the dopant to form the OLED.

(15) Example 14 (Ex14)

The compound 23 is used as the dopant to form the OLED.

(16) Example 15 (Ex15)

The compound 24 is used as the dopant to form the OLED.

(17) Example 16 (Ex16)

The compound 30 is used as the dopant to form the OLED.

TABLE 3 Voltage EQE CIE CIE (V) Cd/A lm/W (%) (X) (Y) Ref 8.85 7.42 2.634.07 0.177 0.297 Ex1 5.95 14.53 7.67 8.65 0.166 0.265 Ex2 4.88 41.8526.91 15.63 0.275 0.549 Ex3 5.88 14.70 7.86 7.06 0.202 0.371 Ex4 5.4512.27 7.07 7.48 0.1647 0.254 Ex5 5.24 10.38 7.74 6.87 0.171 0.203 Ex65.16 10.07 8.01 6.48 0.159 0.190 Ex7 4.91 42.49 26.23 15.32 0.275 0.546Ex8 5.81 12.12 6.77 6.80 0.170 0.263 Ex9 4.86 46.75 28.32 16.84 0.2810.561 Ex10 5.26 13.41 8.84 7.18 0.176 0.202 Ex11 5.03 11.78 8.62 7.340.172 0.189 Ex12 5.96 15.42 8.94 8.05 0.182 0.284 Ex13 5.46 20.68 10.098.81 0.194 0.328 Ex14 5.08 32.84 25.61 11.84 0.264 0.437 Ex15 5.84 11.137.64 6.84 0.168 0.198 Ex16 5.11 38.88 20.04 13.59 0.302 0.482

As shown in Table 3, in the OLEDs using the compounds of the presentdisclosure (Ex1 to Ex16), the properties in the driving voltage, theemitting efficiency and so on are improved.

FIG. 5 is a schematic cross-sectional view of an OLED according to theinvention.

As shown in FIG. 5, the OLED “E” is formed on a substrate (not shown).The OLED “E” includes a first electrode 110 as an anode, a secondelectrode 130 as a cathode, and an organic emitting layer 120therebetween.

Although not shown, an encapsulation film, which includes at least oneinorganic layer and at least one organic layer and covers the OLED “E”,and a cover window on the encapsulation film, may be further formed toform a display device including the OLED “E”. The substrate, theencapsulation film and the cover window may have a flexible propertysuch that a flexible display device may be provided.

The first electrode 110 is formed of a material having a relatively highwork function, and the second electrode 130 is formed of a materialhaving a relatively low work function. For example, the first electrode110 may be formed of indium-tin-oxide (ITO), and the second electrode130 may be formed of aluminum (Al) or Al alloy (AlNd). The organicemitting layer 120 may include red, green, and blue emitting patterns.

The organic emitting layer 120 may have a single-layered structure.Alternatively, to improve the emitting efficiency, the organic emittinglayer 120 includes a hole injection layer (HIL) 121, a hole transportinglayer (HTL) 122, an emitting material layer (EML) 123, an electrontransporting layer (ETL) 124, and an electron injection layer (EIL) 125sequentially stacked on the first electrode 110.

At least one selected from the HIL 121, the HTL 122, the EML 123, theETL 124, and the EIL 125 includes the delayed fluorescence compound inthe Formulas 1-1 or 1-2.

For example, the EML 123 may include the delayed fluorescence compoundin the Formulas 1-1 or 1-2. The delayed fluorescence compound acts asthe dopant, and the EML 123 may further include a host to emit the bluelight. In this instance, the dopant has about 1 to 30 weight % withrespect to the host.

A difference between the HOMO of the host “HOMO_(Host)” and the HOMO ofthe dopant “HOMO_(Dopant)” or a difference between the LUMO of the host“LUMO_(Host)” and the LUMO of the dopant “LUMO_(Dopant)” is less than0.5 eV. (|HOMO_(Host)−HOMO_(Dopant)|≤0.5 eV or|LUMO_(Host)−LUMO_(Dopant)|≤0.5 eV.) In this instance, the chargetransfer efficiency from the host to the dopant may be improved.

For example, the host, which meets the above condition, may be selectedfrom materials in Formula 9. (Bis[2-(diphenylphosphino)phenyl]etheroxide (DPEPO), 2,8-bis(diphenylphosphoryl)dibenzothiophene (PPT),2,8-di(9H-carbazol-9-yl)dibenzothiophene (DCzDBT),m-bis(carbazol-9-yl)biphenyl (m-CBP),Diphenyl-4-triphenylsilylphenyl-phosphine oxide (TPSO1),9-(9-phenyl-9H-carbazol-6-yl)-9H-carbazole (CCP) in order.)

The triplet energy of the dopant is smaller than the triplet energy ofthe host, and a difference between the singlet energy of the dopant andthe triplet energy of the dopant is less than 0.3 eV. (ΔE_(ST)≤0.3 eV.)As the difference “ΔE_(ST)” is smaller, the emitting efficiency ishigher. In the delayed fluorescence compound of the present invention,even if the difference “ΔE_(ST)” between the singlet energy of thedopant and the triplet energy of the dopant is about 0.3 eV, which isrelatively large, the excitons in the singlet state “S1” and theexcitons in the triplet state “T1” can be transited into theintermediate state “I1”.

On the other hand, the delayed fluorescence compound of the presentinvention may act as a host in the EML 123, and the EML 123 may furtherinclude a dopant to emit the blue light. In this instance, the dopanthas approximately 1 to 30 weight % with respect to the host. Since thedevelopment of the blue host having excellent properties isinsufficient, the delayed fluorescence compound of the present inventionmay be used as the host to increase the degree of freedom for the host.In this instance, the triplet energy of the dopant may be smaller thanthe triplet energy of the host of the delayed fluorescence compound ofthe present disclosure.

The EML 123 may include a first dopant of the delayed fluorescencecompound of the present disclosure, a host, and a second dopant. Theweight % summation of the first and second dopants may be about 1 to 30to emit the blue light. In this instance, the emitting efficiency andthe color purity may be further improved.

In this instance, the triplet energy of the first dopant, i.e., thedelayed fluorescence compound of the present disclosure, may be smallerthan the triplet energy of the host, and larger than the triplet energyof the second dopant. In addition, a difference between the singletenergy of the first dopant and the triplet energy of the first dopant isless than 0.3 eV. (ΔE_(ST)≤0.3 eV.) As the difference “ΔE_(ST)” issmaller, the emitting efficiency is higher. In the delayed fluorescencecompound of the present disclosure, even if the difference “ΔE_(ST)”between the singlet energy of the dopant and the triplet energy of thedopant is about 0.3 eV, which is relatively large, the excitons in thesinglet state “S₁” and the excitons in the triplet state “T₁” can betransited into the intermediate state “I₁”.

As mentioned above, since the delayed fluorescence compound of thepresent disclosure includes the electron donor moiety and the electronacceptor moiety with or without another electron donor moiety, and theelectron donor moiety of acridine forms a large steric hindrance withthe electron acceptor moiety, the emitting efficiency is improved. Inaddition, the dipole from the first and second electron donor moietiesto the electron acceptor moiety is generated such that the dipole momentin the molecule is increased. As a result, the emitting efficiency isfurther improved. Moreover, in the delayed fluorescent compound of thepresent invention, the excitons in the triplet state are engaged in theemission such that the emitting efficiency of the delayed fluorescentcompound is increased.

Since a gap or a distance between the electron donor moiety and theelectron acceptor moiety is increased due to the linker, an overlapbetween HOMO and LUMO is reduced such that a gap (ΔE_(ST)) between thetriple energy and the singlet energy is reduced. In addition, due to thesteric hindrance of the linker, the red shift problem in the lightemitted from the emitting layer including the delayed fluorescencecompound is decreased or minimized.

Accordingly, the OLED and the display device using or including thedelayed fluorescence compound of the present disclosure has an advantagein the emitting efficiency.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the embodiment of theinvention without departing from the spirit or scope of the invention.Thus, it is intended that the embodiment of the invention cover themodifications and variations of this invention provided they come withinthe scope of the appended claims and their equivalents.

What is claimed is:
 1. An organic light emitting diode, comprising: an organic emitting layer including a delayed fluorescence compound of Formula 1:

wherein X₁ comprises C3 heterocyclic group through C12 heterocyclic group, and wherein the C3 heterocyclic group through C12 heterocyclic group comprises at least two nitrogen atoms.
 2. The organic light emitting diode according to claim 1, wherein X₁ is one of Formulas 2-1 to 2-3:


3. The organic light emitting diode according to claim 1, wherein m is 1, and L₁ is Formula 3:

wherein each of R₅ and R₆ in the Formula 3 comprises one of hydrogen and C1 alkyl through C20 alkyl.
 4. The organic light emitting diode according to claim 1, wherein a difference between a singlet energy of the delayed fluorescence compound and a triplet energy of the delayed fluorescence compound is less than 0.3 eV.
 5. The organic light emitting diode according to claim 1, further comprising: a first electrode; and a second electrode, wherein the organic emitting layer is between the first electrode and the second electrode.
 6. The organic light emitting diode according to claim 1, wherein the organic emitting layer further includes a host, and the delayed fluorescence compound is used as a first dopant.
 7. The organic light emitting diode according to claim 6, wherein a difference between a highest occupied molecular orbital (HOMO) of the host and a HOMO of the first dopant or a difference between a lowest unoccupied molecular orbital (LUMO) of the host and a LUMO of the first dopant is less than 0.5 eV.
 8. The organic light emitting diode according to claim 6, wherein the host is selected from:


9. The organic light emitting diode according to claim 8, wherein a triplet energy of the first dopant is smaller than a triplet energy of the host, and a difference between a singlet energy of the first dopant and the triplet energy of the first dopant is less than 0.3 eV.
 10. The organic light emitting diode according to claim 6, wherein the organic emitting layer further includes a second dopant.
 11. The organic light emitting diode according to claim 10, wherein a weight % summation of the first dopant and the second dopant is about 1 to
 30. 12. The organic light emitting diode according to claim 10, wherein a triplet energy of the first dopant is smaller than a triplet energy of the host and larger than a triplet energy of the second dopant.
 13. The organic light emitting diode according to claim 1, wherein the organic emitting layer includes a hole injection layer (HIL), a hole transporting layer (HTL), an emitting material layer (EML), an electron transporting layer (ETL), and an electron injection layer (EIL), and wherein at least one of the HIL, the HTL, the EML, the ETL, and the EIL includes the delayed fluorescence compound.
 14. The organic light emitting diode according to claim 1, wherein the organic emitting layer further includes a dopant, and the delayed fluorescence compound is used as a host.
 15. The organic light emitting diode according to claim 14, wherein the dopant has approximately 1 to 30 weight % with respect to the host.
 16. The organic light emitting diode according to claim 14, wherein a triplet energy of the dopant is smaller than a triplet energy of the host. 